SUMMARY:Reversible cerebral vasoconstriction syndrome is a clinical and radiologic syndrome that represents a common presentation of a diverse group of disorders. The syndrome is characterized by thunderclap headache and reversible vasoconstriction of cerebral arteries, which can either be spontaneous or related to an exogenous trigger. The pathophysiology of reversible cerebral vasoconstriction syndrome is unknown, though alterations in cerebral vascular tone are thought to be a key underlying mechanism. The syndrome typically follows a benign course; however, reversible cerebral vasoconstriction syndrome may result in permanent disability or death in a small minority of patients secondary to complications such as ischemic stroke or intracranial hemorrhage.ABBREVIATIONS: RCVS ϭ reversible cerebral vasoconstriction syndrome; PRES ϭ posterior reversible encephalopathy syndrome

SUMMARY:The diagnostic evaluation of a patient with reversible cerebral vasoconstriction syndrome integrates clinical, laboratory, and radiologic findings. Imaging plays an important role by confirming the presence of cerebral vasoconstriction; monitoring potential complications such as ischemic stroke; and suggesting alternative diagnoses, including CNS vasculitis and aneurysmal subarachnoid hemorrhage. Noninvasive vascular imaging, including transcranial Doppler sonography and MR angiography, has played an increasingly important role in this regard, though conventional angiography remains the criterion standard for the evaluation of cerebral artery vasoconstriction. Newer imaging techniques, including high-resolution vessel wall imaging, may help in the future to better discriminate reversible cerebral vasoconstriction syndrome from primary angiitis of the CNS, an important clinical distinction. ABBREVIATIONS:PACNS ϭ primary angiitis of the CNS; RCVS ϭ reversible cerebral vasoconstriction syndrome; TCD ϭ transcranial Doppler sonography; VWI ϭ

BackgroundThe first pass effect has been recently reported as a predictor of good clinical outcome after stroke thrombectomy. We evaluate the first pass effect on outcome and the influence of revascularization in these and other patients.MethodsWe performed a retrospective analysis of a prospectively maintained database on anterior cerebral circulation stroke thrombectomy cases from April 2012 to April 2018. Data compiled included patient demographics, presenting National Institutes of Health Stroke Scale score, vessel occlusion site, thrombectomy procedural details, and 90 day modified Rankin Scale scores.Results205 patients were included. The numbers of patients who underwent one, two, three, four, five, and six passes were 69, 70, 55, 9, 1, and 1, respectively. Successful revascularization was achieved in 87%, 83%, and 64% of patients in the one, two, and 3 or more passes groups, respectively (p=0.002). Good functional outcome was inversely correlated with number of passes when comparing the one, two, and three or more passes groups (54%, 43%, 29%; P=0.014). In patients with full revascularization, there was no significant difference in good functional outcomes between the one, two, and three or more passes groups (64%, 65%, 50%; P=0.432). Number of passes was not an independent negative predictor of good clinical outcome (OR 1.66, 95% CI 0.82 to 3.39; P=0.165).ConclusionsFirst pass thrombectomy patients have better functional outcomes compared with beyond-first pass patients. This effect is related at least in part to a higher rate of revascularization in one pass patients. Revascularization beyond the first pass should continue to be the goal of stroke thrombectomy.

When using SRs for intracranial stroke thrombectomy, the concurrent use of IACs is associated with a decrease in procedural time and thrombectomy attempts compared with use of SRs alone.

Progressive stagnation or occlusion of covered side branches or target aneurysm are early angiographic signs of acute thrombus formation following PED placement and should prompt immediate treatment with a glycoprotein IIb/IIIa inhibitor. Platelet inhibition testing may help identify those patients who are at an increased risk for this complication.